Arsenal manager Mikel Arteta has confirmed Mohamed Elneny and Thomas Partey will spend extended spells on the sidelines.
The Gunners managed without the duo against Aston Villa on Wednesday, taking out a 2-1 victory at the Emirates.
On Elneny, Arteta said: "That's not good news, we still need him to see our specialist but I'm afraid we're going to lose Mo for a while."
Asked about Partey, the Spaniard added: "He's going to be out for a while but we don't know how long that period is going to be.
"Obviously, it's not the first injury that he's had in that area so it is a recurring injury, so it's one for the doctors to put a timeline on it and see how he goes."
Arteta also confirmed that Arsenal would look to the transfer market to replace Elneny and Partey before Thursday's deadline.